RFR: 8171855: Move package name transformations during module bootstrap into VM
claes.redestad at oracle.com
Mon Jan 2 18:27:43 UTC 2017
during jigsaw bootstrap, package names - represented in external form,
"java.lang" - are transformed into VM internal form, "java/lang",
before calling into the VM.
This, however, can effectively be moved into the VM, which removes the
need to generate a lot of short-lived strings during bootstrap and heat
up various String.replace-related methods. This has a noticeable impact
on startup metrics.
JPRT -testset hotspot pass, and I've prepared to push this into jdk9/hs
if there are no objections.
Char-based replace on a UTF-8 source should be correct as long as the
from and to chars are ASCII (0x00 through 0x7F). A more general method
would be needed to safely deal with char values above 0x7F, so adding
some asserts to that effect should be considered.
More information about the jigsaw-dev